maker who allegedly built the underwear bomb used to nearly blow up an airliner on christmas day at detroit metropolitan airport. >> all of our explosive detection equipment which screens over a million checked bags every day just in the u.s. wasn't calibrated to detect that. >> reporter: there are a few specific details about what kind of attack could be in the works. analysts believe somewhere in yemen is the most likely target and ominously warn it could be anywhere in the arc of mostly muslim countries. already the government plans to build 22 consulates and embassies beginning tomorrow. the state department is alerting u.s. citizens for what it calls the continued potential for terrorist attacks with public transportation and other infrastructures as the terror targets. >> obviously it's important that we ensure that everyone is safe overseas. >> other western countries are affected by this as well. britain has closed its embassy in yemen and is urging all of its citizens to leave the country. that travel alert, by the way, until the end of the month. anthony? >> jeff pegues in our was